Vessel Sealing Instrument with Reduced Thermal Spread and Method of Manufacture Therefor

Abstract

An electrosurgical vessel sealing instrument having a first and a second opposing jaw member at a distal end thereof, wherein each jaw member includes a jaw housing, a seal plate having a tissue contacting surface and a side wall, and an insulating region disposed on the side wall of the seal plate. The instrument includes the ability to move the jaw members relative to one another from a first position wherein the jaw members are disposed in spaced relation relative to one another to a second position wherein the jaw members cooperate to grasp tissue. The insulating region enables precision overmolding of the jaw housing to the seal plate, while advantageously reducing thermal spread and edge cutting during vessel sealing procedures.

Description

BACKGROUND[0001]1. Technical Field[0002]The present disclosure relates to electrosurgical instruments and methods for performing surgical procedures and, more particularly, to an electrosurgical vessel sealing instrument with a jaw assembly having one or more insulating members associated with the sealing plate that provide reduced thermal spread and reduced edge cutting while enabling improved dimensional tolerances during the prototyping and manufacturing process.[0003]2. Background of Related Art[0004]A hemostat or forceps is a simple pliers-like tool that uses mechanical action between its jaws to constrict tissue and is commonly used in open surgical procedures to grasp, dissect and / or clamp tissue. Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize and / or seal vascular tissue.[0005]Using electrosurgical forceps, a surgeon can elect to seal, cauterize, coagula...

AI Technical Summary

Benefits of technology

The innovation described in this patent is a sealing device used in a surgical instrument. The device includes a seal plate and insulating layer, which are attached to the instrument. The seal plate has a reverse surface that has ribs and valleys, which are engaged with corresponding features of the insulator. This arrangement provides optimal current paths while minimizing thermal spread and collateral damage, resulting in a higher quality seal and reduced risk of injury to adjacent tissue. The insulating substrate and seal plate also isolates the two electrically opposing electrodes within the instrument, reducing the possibility of unintended current travel. Overall, this innovation improves the functionality and safety of the sealing device.

Problems solved by technology

Excessive thermal energy should not be allowed to spread to adjacent areas of tissue, as this may diminish the integrity of a resulting seal since the energy required to form the seal is dissipated into the surrounding tissue rather than into the region intended to be sealed.

It has been found that reducing the height of the seal plate side walls may minimize thermal spread, yet, too much of a reduction in sidewall height may result in excessive current concentrations resulting in increased edge cutting.

Using prior art overmolding techniques, it is difficult to maintain the tolerances necessary to form a jaw member having the desired minimal thermal spread and minimal edge cutting properties since variations in edge height were unavoidable.

During product development cycles, where numerous and different prototypes may be built, the overmolding process may not be cost-effective and may yield unsatisfactory results, particularly when a prototype jaw member needs to be fabricated precisely for evaluation purposes.

Preferably, the geometry of the insulating substrate and seal plate also isolates the two electrically opposing electrodes formed by opposing seal plates within a pair of jaws from one another, thereby reducing the possibility that tissue or tissue fluids can create an unintended bridge or path for current travel.

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